Convicted Oklahoma City bomber Timothy McVeigh provided a sketched diagram of the ammonium nitrate and fuel oil bomb he ferried to the Alfred P. Murrah Federal Building six years ago, which shows a device larger than federal officials have stated.

McVeigh, who made the drawing himself for his defense team in 1995 during lawyer-client interviews, also coached his defense team through additional sketches of the device that federal officials have blamed for all of the devastation to the Murrah Building April 19, 1995.

Details of the sketches, as well as copies of them, were provided to WND by Oklahoma-based lawyer and investigative journalist J.D. Cash, who said he first published his information in a local newspaper, the McCurtain Daily Gazette, a small Oklahoma-based newspaper, last December.

Cash said his information was “derived from internal legal memoranda prepared by” McVeigh’s lawyers and those of his sister, Jennifer, “and/or affidavits produced by the FBI” in Freedom of Information Act requests.

The sketches were reportedly made in May of 1995, just weeks after the attack on the Murrah building that claimed the lives of 168 people.

Cash, in the first of a series of five articles written for the McCurtain Daily Gazette, noted that “careful scrutiny of the documents corroborates much of the government’s theory of what the primary components of the deadly device were. …”

Experts who analyzed the details provided in the McVeigh sketch and those of his defense team found that the bomb was larger and contained substantially more destructive power than previously thought or reported.

Also, Cash noted, “records of comments McVeigh made indicate the truck bomb was not completed in central Kansas, as the government has long believed,” but rather was completed “in a hurried fashion” just minutes before it went off in front of the Murrah building.

Sophisticated device

According to the McVeigh drawings, the Ryder rental truck used to transport the bomb contained 13 large plastic barrels of varying colors.

Six of the barrels were white, six were black, and one was blue; also, McVeigh indicated that three other blue steel barrels were also in the cargo hold of the truck.

Cash reported that McVeigh said the white barrels were bought from a farm co-op in Hillsboro, Kan., while the black ones were purchased in Florence, Kan. The remaining blue plastic barrel was bought in Council Grove, Kan.

In the aftermath of the bombing, experts and government forensic analysts formed different opinions about the bomb’s make-up. Some speculated that shards of plastic found in the rubble were part of the bomb, while others said they may have come from toys that were located in the Murrah Building’s daycare center.

“But these documents indicate the bombers ‘scavenged’ different-colored barrels to build the device,” Cash said, a fact that “could weigh heavily in future prosecutions” of other, so far unindicted, suspects.

While the government has speculated that the bomb was completely constructed away from Oklahoma City by McVeigh and co-conspirator Terry Nichols, then transported about 250 miles to its final destination by McVeigh alone, experts interviewed by Cash say the bomb’s design makes that theory highly unlikely.

And, Cash said, the way the barrels full of mixture were placed suggested that the bombers arranged them in such a way as to form a makeshift “shaped charge” that would aim more of the blast at the Murrah building.

The configuration of barrels was then set off by 350 pounds of “Tovex Blastrite Gel,” or “sausages,” as McVeigh referred to them in interviews, Cash said.

“Finally, a simple time-delayed fuse led from the cab of the truck to the non-electric [Primadet] blasting caps,” which were set up to “initiate the ‘sausages’ with millisecond precision,” Cash wrote.

Nine of the 13 plastic barrels were filled with ammonium nitrate and nitro-methane that sources said were purchased from Tim Chambers, a fuel salesman at a racetrack outside of Dallas, Texas, in the fall of 1994. The other four were mixed with the fertilizer and about four gallons of diesel fuel, because McVeigh, according to Cash, said that there had not been enough nitro-methane to mix all 13 barrels.

Chambers testified at McVeigh’s trial that he sold three blue steel barrels full of nitro-methane to a man fitting McVeigh’s description. McVeigh later told his defense counsel that the three empty barrels of nitro-methane were added to the 13 plastic barrels “as a decoy,” Cash said.

After discovering there was not enough fuel to finish the bomb, Cash said McVeigh told his defense team that nine unopened 50-pound bags of fertilizer were left stacked along the driver’s side in the cargo area.

“With this disclosure, the overall amount of fertilizer that McVeigh can account for is far greater than what was earlier believed used in the bomb,” Cash wrote. “A shortage of fuel would have been easy to remedy had the bomb really been built in Kansas on the day before the bombing, as prosecutors believed. There were dozens of service stations along the route from Junction City, Kan.,” where McVeigh was known to have stayed the day before, “to Oklahoma City and plenty of time and opportunity … to purchase additional diesel fuel” to make up for the nitro-methane shortage.

Cash said an expert with “extensive experience” in testing improvised explosive devices for various government counterterrorism studies examined the McVeigh sketches and details, concluding that “the bomb had in excess of 6,200 pounds of ‘energetic materials’ – equivalent to 5,000 pounds of TNT.”

That estimate, Cash said, exceeded the federal government’s estimate by about 25 percent.

Also, experts told Cash that the device described by McVeigh would have been far too unstable to transport 250 miles in the back of a bumpy rental truck.

“Whether the caps were electric or non-electric, both are too unstable to transport long distances [while] attached to the [explosive] boosters,” Larry Gier, an Oatman, Ariz., mining engineer experienced with such devices told Cash.

“Diesel fuel can be added to the fertilizer well ahead of time” before the device is set off, Gier added, “but nitro-methane is far too unstable and easily degradable to transport long distances after mixing it with explosive-grade fertilizer.”

Doubts about second bomb

Because of the size of the bomb, as detailed in the McVeigh sketches, and because of the extensive damage caused to a number of structures surrounding the Murrah building, Cash told WND in an interview that he was not convinced there were other devices planted inside.

However, citing research for another project he said he could not yet discuss, Cash said federal law enforcement agencies – many of which were located inside the Murrah building – have a history of improperly storing explosive devices in their offices. And one or more of those devices, he said, could have caused a secondary but unintended explosion within the Murrah building.

“My opinion is, we may never be able to prove it because they took all the evidence and buried it” shortly after the explosion, he said.

“I have no knowledge of that. I have never heard of that before,” Steve Berry, a spokesman for the FBI, told WND. He also said he “had no knowledge” of any other explosive devices planted at the Murrah Building.

“All we reported was McVeigh’s device,” Berry said.

Jim Crandell, an inspector and former field agent for the Bureau of Alcohol, Tobacco and Firearms, also denied knowledge of any other devices in the building.

“I can’t comment at all on whether there might have been additional explosives in the building because I simply don’t know,” Crandell told WND. But, he said, it was ATF’s policy “not to store explosives in any of our offices.”

“We maintain explosives bunkers for” storage of explosive materials, he added, noting that ATF sometimes uses local storage facilities operated by local law enforcement agencies. He did say that the agency stored some of its own weapons at its offices, and he denied that ATF agents were tipped to the bombing the morning it occurred.

Other experts disagree with Cash’s theory.

Former Air Force Gen. Ben Partin, an explosives expert with decades of warhead design and testing experience, concluded in a 1995 report that, based on the extent of damage, other devices had to have been planted inside.

Witnesses reported seeing strange, unfamiliar people inside the Murrah Building in the days leading up to the bombing.

Some witnesses, as reported by an Oklahoma bombing investigative committee headed up by former state Rep. Charles Key, said they overheard ATF officials the morning of the bombing discussing a page they had received to stay out of the Murrah Building.

Key and the committee are scheduled to release a comprehensive 500-page report concluding that the government had prior knowledge and that McVeigh did not act alone in the bombing.